Sony XA-5400es player...Giant Killer or just Ok?

Get a Sony 595 as mentioned above with the TRL mods. They do come up used. I have a Sony 900s with the TRL mods and it runs all over the 5400 IMHO.. The Oppo 95 is also a better choice. I had the 5400 and it is OK, not great.

A simple DAC (Wyred 4 Sound) or nicer unit (LINN DS), will trash that CD player in a very big way. And you will not have to touch a CD again either. Do not buy ANY CD player.

I suggest "do not go to computer audio yet" and get a CD player :-)

Computer Audio does not sound as good as a great CD player based on my recent experience - at least not yet. Also, it has so many twists, turns, changes, updates etc.. that I would give it more time to mature a bit.

As mentioned, this has been hashed over many times but if you're going unmodified and listen mostly to redbook, I'd go with an Oppo 95. The Sony is probably better on SACD but I'm guessing redbook will be your main diet. Of course with the Oppo, you also get video.

If you're considering the Modwright route down the road and audio is your main concern, I'd definitely go with the Sony.

My Sony 5400 has been reliable and has performed without a glitch. I have a unit that has been modded by The Upgrade Company and really enjoy it. I am not aware of reliability issues in general for this model. Regarding the claim of "giant killer" I cannot comment because I have not made any direct comparisons. But it is sonically different (perhaps better) in some ways than my previous McCormack UDP-1 Deluxe, which is no slouch. Hope that helps somewhat.